It has been suggested that nighttime nicotine withdrawal may help to explain why tobacco cigarette smokers are more likely than nonsmokers to experience clinically significant insomnia. There is also reason to believe that intolerance for withdrawal symptoms could play a role in withdrawal-related sleep disturbance. However, we are not aware of any previous research that examined whether smokers who endorse greater intolerance for smoking abstinence also report greater difficulty initiating and/or maintaining sleep. To address this question, 224 adult cigarette smokers (42.9% female, Mcigarettes per day = 21.3) completed the baseline portion of an experimental study that included assessment of current/historical smoking behavior, perceived intolerance for smoking abstinence, and insomnia severity and impact on functioning. The results indicated that, after accounting for general distress intolerance and sociodemographic factors, smokers who endorsed greater intolerance for nicotine withdrawal also reported greater insomnia severity and impact. Logistic regression further revealed that, for every 1-point increase in nicotine withdrawal intolerance scores, smokers were nearly twice as likely to score above threshold for clinically significant insomnia (p = .001). Collectively, these initial findings suggest that intolerance for nicotine withdrawal may warrant consideration as a potentially modifiable mechanistic factor in comorbid insomnia and nicotine/tobacco dependence. (PsycInfo Database Record (c) 2022 APA, all rights reserved).